Looking for the best backup software?

The essentials of a good backup

The three functions essential to any good backup program are:

image backup and restore

files and folders backup and restore

disaster recovery.

The software should also be flexible and easy to use, so you can create a backup procedure designed to fit your needs. Our buying guide details everything you need to know so you can find the ideal program.

How you'll use your backup

Typically you'll use backup software to:

restore files/folders following accidental deletion or corruption

restore a drive to a previous state, a working system that's infected by a virus causing data loss

repair problems caused by operating system (OS) failure

restore to a new drive. You can restore a PC's entire hard drive contents to a new hard drive when the old one, or part of the hardware, has failed, or when the system will not boot to the desktop (disaster recovery).

The first and second examples will usually let you access your desktop so you can recover lost files or roll the operating system back to an earlier state. Three and four are typically used when your PC cannot start, which means rebuilding the operating system, programs and files on the same computer. This is often referred to as disaster recovery.

But did you know you can also use backup software to more easily upgrade your PC? A full backup lets you restore everything to a new hard drive in the same computer, even if the original is still working. Say you're using a 500GB drive, for example, and you want to upgrade to a 2TB drive. Most backup programs will let you create an exact duplicate or "clone" your system, so you can copy it onto the larger drive.

Things get a bit trickier however, when you want to restore your data to an entirely different computer, because you're working with different components (e.g. CPU, motherboard) and system drivers. In this case, you'll need to find a program that can 'clone' your drive and restore it to a different computer.

File backup vs disk imaging

Most backup programs will duplicate your data in one of two ways:

File/folder backup: Here individual files and folders are duplicated. Sometimes they are stored in a package that can only be read or unpacked by the backup software in question.

Disk image: Essentially a screenshot in time of your entire system. You can use a disk image to restore your computer to the state it was in when the image was created, with all programs, files, folders and preferences in place.

They can do this using a variety of methods depending on the program:

Full backup: As the name suggests, this will duplicate all of the files and folders on your computer. A full backup is time consuming, but it's the required first step, even if subsequent backups only add the new or different files added to the hard drive since the full backup.

Incremental backup: This backs up files that have changed or been added since the previous backup, while leaving unchanged files untouched. It requires less time and space than doing a full backup each time, and also gives you the option to roll back to earlier versions of files.

Differential backup: This duplicates all files since the full backup, with the differential backup file growing each time. Restoring only requires the full backup plus the differentiated backup file.

Clone backup (disk image): Creates an exact virtual copy of the drive being backed up, including all files, settings and drive structure.

In most cases, programs will not continually backup your data. Instead they work on regularly timed intervals, while some perform near-continuous backups, with incremental updates on an hourly basis or even more often. Those with a continuous backup will back up as files are changed, keeping your backup always up to date.

Where to store your backup

We all know we should back up our data regularly, if not continuously. You can use the backup software supplied with the operating system or third-party software and, ideally, automate it so it's set-and-forget. But what do you back up to? Backup software gives you two broad options:

Physical storage: These programs usually let you copy your data to CD/DVD or an external thumb/hard drive (local media). Some can also backup to NAS (network attached storage), FTP (external file server storage) and even tape.

Cloud storage: This is becoming an increasingly common alternative to local media, and while it offers advantages such as offsite backup, increased security and the freedom to access your data anywhere, cloud storage services usually have subscription fees. These increase as you add more space which, when coupled with the costs of internet access, can end up being a relatively expensive option. Some dedicated PC desktop backup programs support cloud backup as well as local backup. There are also cloud services for online backup, some of which can also back up to a local drive.

Types of storage media

While most forms of electronic storage are quite reliable, none are infallible.

Hard drives can last for quite a few years in normal usage, or they can fail at any minute and the same applies to Flash storage and SSDs (solid­-state drives). Because hard drives are high capacity and cheap, they're the first line of defence against data loss. A 2TB (terabyte) portable hard drive can commonly be had at major retailers for under $100 (double that for 4TB), while an 8TB desktop model can cost as little as $350. SSDs are super-fast but a 1TB model will cost around $600. The trade-off is between speed, capacity and cost. See our Portable media storage device reviews for how we rate a range of hard drives, SSDs, and USB flash drives.

DVDs can be reliable for years, but only if handled and stored carefully. Discs are cheap (under $1/disc) but low capacity (4.7GB) and only useful for archiving small projects.

Cloud storage/backup gives you secure offsite storage backup accessible from internet connected devices anywhere. But it isn't recommended as your only form of backup, largely due to the long time it takes to upload/download large amounts of data (think terabytes) and the ongoing subscription cost of cloud services ($60–$170/year). It's best used for your most important files (think gigabytes) and can be a valuable part of your overall plan.

Long­-term security of your data is more about the quality of your backup method than the inherent reliability of the storage medium, as long as you buy good quality (avoid super-cheap no-name brands). The best practice for peace of mind is to have three copies of your data if possible, in different media/places so that no one data disaster can wipe everything out.

A cost-effective and secure strategy includes the following:

External hard drive: Back up your computer to an external hard drive (so you have at least two copies of the data).

Cloud: Also back up just your most important data to the cloud.

Archived data: If you archive data (copy it to an external drive, for example, and remove it from the computer) you should have a backup of the archive stored offsite. If you add to the archive, you need to make sure you update both sets of data.

Cycle your backups: Your backup drive should regularly be cycled (swapped over) with another backup drive and kept offsite. This keeps your offsite backup up to date. This should also be the case if you use a NAS drive.

The payoff

A good backup strategy that includes offsite backup will see you through fire, flood, theft, computer failure. It will also protect you against ransomware attacks that can lock up all your data, including attached backup drives. Creating the right combination of backup software and storage type, then keeping it up to date, will pay you big dividends in peace of mind.